A frit-sealing apparatus for a cathode-ray tube has a nozzle portion being inserted into and withdrawn later from the cathode-ray tube supported in a certain position; a guide block for supporting the nozzle portion; a guide rod for supporting the guide block so as to slide in directions in which the nozzle portion is inserted and withdrawn; and a rotation restriction member being in contact with an outer surface of the guide block, thereby restricting rotation of the guide block.